Turbine disk

Abstract

A turbine rotor disk for a gas turbine engine includes a disk rotationally disposed about a central axis. The disk includes a number of blade posts, tabs and slots circumferentially disposed about a rim portion of the disk. The tabs each include a blade post transition portion, a slope portion radially inward of the blade transition portion and a face portion radially inward of the slope portion. The blade posts, tabs and slots are circumferentially oriented about the rim portion such that a tab or slot is positioned radially inward of each blade post.

What is claimed is: 
     
       1. A turbine rotor, comprising:
 a disk rotationally disposed about a central axis, the disk including a first rim portion and a second rim portion, the second rim portion disposed radially inward of the first rim portion; 
 a first blade post disposed proximate the first rim portion; 
 a first tab disposed proximate the second rim portion, the first tab positioned radially inward of the first blade post and having a first axial profile in a circumferential direction; and 
 a slot disposed circumferentially adjacent the first tab, the slot having a roof portion that defines a roof angle extending radially outward with respect to the central axis, the roof angle ranging from 35 degrees to 45 degrees, 
 wherein the first axial profile of the first tab includes a blade post transition portion that connects two different axially facing surfaces, the blade post transition portion disposed circumferentially adjacent a radially inward most branch of a plurality of branches spaced radially between a base and a tip of the first blade post and at a radial distance from the central axis equal to that of the radially inward most branch, a slope portion radially inward of the blade post transition portion and a face portion radially inward of the slope portion. 
 
     
     
       2. The turbine rotor of  claim 1 , wherein the tip and the base of the first blade post define a length in a radial direction and wherein the blade post transition portion is disposed at a location between 25% and 50% of the length in a radially outward direction. 
     
     
       3. The turbine rotor of  claim 2 , wherein the blade post transition portion has a radius of curvature of 0.100 inches to 0.300 inches. 
     
     
       4. The turbine rotor of  claim 2 , wherein the slope portion of the first tab extends radially inward from the blade post transition portion at an angle with respect to the central axis and wherein the slope portion merges with the face portion. 
     
     
       5. The turbine rotor of  claim 4 , wherein the slope portion extends radially inward at an angle of 60 degrees to 65 degrees with respect to the central axis. 
     
     
       6. The turbine rotor of  claim 4 , wherein the slope portion extends radially inward at an angle of 60 degrees to 65 degrees with respect to the central axis and wherein the face portion extends radially inward at an angle of 85 degrees to 95 degrees with respect to the central axis. 
     
     
       7. The turbine rotor of  claim 6 , further comprising:
 a second blade post disposed circumferentially adjacent the first blade post; and 
 a second tab disposed circumferentially adjacent the first tab, the second tab positioned radially inward of the second post and having a second axial profile identical in shape to the first axial profile,
 wherein the slot is disposed between the first tab and the second tab. 
 
 
     
     
       8. A turbine rotor, comprising:
 a disk rotationally disposed about a central axis; 
 a plurality of blade posts disposed on and spaced circumferentially about a radially outer portion of the disk; 
 a plurality of tabs disposed on and spaced circumferentially about a portion of the disk radially inward from the radially outer portion of the disk, each tab having an axial profile in a circumferential direction; and 
 a slot disposed between adjacent pairs of the plurality of tabs, the slot having a roof portion that defines a roof angle extending radially outward with respect to the central axis, the roof angle ranging from 35 degrees to 45 degrees, 
 wherein the axial profile of each one of the plurality of tabs includes a blade post transition portion that connects two different axially facing surfaces, the blade post transition portion disposed circumferentially adjacent a radially inward most branch of a plurality of branches spaced radially between a base and a tip of each of the plurality of blade posts and at a radial distance from the central axis equal to that of the radially inward most branch, a slope portion radially inward of the blade post transition portion and a face portion radially inward of the slope portion. 
 
     
     
       9. The turbine rotor of  claim 8 , wherein the slope portions extend radially inward from the blade post transition portions at an angle with respect to the central axis and wherein the slope portions merge with the face portions. 
     
     
       10. The turbine rotor of  claim 9 , wherein the blade post transition portions have a radius of curvature of 0.100 inches to 0.300 inches. 
     
     
       11. The turbine rotor of  claim 10 , wherein the slope portions extend radially inward at an angle of between 60 degrees and 65 degrees with respect to the central axis. 
     
     
       12. The turbine rotor of  claim 11 , wherein the slope portions extend radially inward at an angle of 62 degrees with respect to the central axis and wherein each corresponding face portion extends radially inward at an angle of 90 degrees with respect to the central axis. 
     
     
       13. The turbine rotor of  claim 8 , wherein the roof angle ranges from 39.5 degrees to 40.5 degrees. 
     
     
       14. A turbine rotor, comprising:
 a disk rotationally disposed about a central axis; 
 a plurality of blade posts disposed on and spaced circumferentially about a radially outermost portion of the disk; 
 a plurality of tabs disposed on and spaced circumferentially about a portion of the disk radially inward from the radially outermost portion of the disk, each tab having an axial profile in a circumferential direction; and 
 a plurality of slots interspersed between adjacent pairs of tabs, each of the plurality of slots having a roof portion that defines a roof angle extending radially outward with respect to the central axis, the roof angle ranging from 35 degrees to 45 degrees, 
 wherein the axial profile of each one of the plurality of tabs includes a blade post transition portion that connects two different axially facing surfaces, the blade post transition portion disposed circumferentially adjacent a radially inward most branch of a plurality of branches spaced radially between a base and a tip of each of the plurality of blade posts and at a radial distance from the central axis equal to that of the radially inward most branch, a slope portion merging with and extending radially inward of the blade post transition portion and a face portion merging with and extending radially inward of the slope portion. 
 
     
     
       15. The turbine rotor of  claim 14 , wherein the blade post transition portions have a radius of curvature of 0.100 inches to 0.300 inches, wherein the slope portions extend radially inward at an angle of 60 degrees to 65 degrees with respect to the central axis and wherein the face portions extend radially inward at an angle of 85 degrees to 95 degrees with respect to the central axis.